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This is the same pattern used > by queue_folios_pte_range() (skipping zone device without failing). > > Fixes: a30b48bf1b24 ("mm/migrate_device: implement THP migration of zone device pages") > Cc: stable@vger.kernel.org > Signed-off-by: Gregory Price (Meta) > --- > mm/mempolicy.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/mm/mempolicy.c b/mm/mempolicy.c > index 3498a5651d50f..3418b5664dcf8 100644 > --- a/mm/mempolicy.c > +++ b/mm/mempolicy.c > @@ -662,6 +662,8 @@ static void queue_folios_pmd(pmd_t *pmd, struct mm_walk *walk) > return; > } > folio = pmd_folio(pmdval); > + if (folio_is_zone_device(folio)) > + return; > if (is_huge_zero_folio(folio)) { > walk->action = ACTION_CONTINUE; > return; > -- > 2.53.0-Meta > A similar patch was sent out earlier, but that was only for zone device private THP, we don't support migration of device coherent THP today (we should add support). The patch itself makes sense Reviewed-by: Balbir Singh